Method of printing



NOV. 29, 1938. w MATUSCHKE v2,138,703

METHOD OF PRINTING Filed Oct. 12, 1936 fir/7e d Fe/ferd H mm 541M770m\\\\\l\ Mk v Z p f ATTORNEYS Patented Nov. 29, 1938 UNITED STATESPATENT OFFICE April 11, 1935 10 Claims. (Cl. 101-211) This inventionrelates to a method of printing with a typographic press, 1. e., onewherein the printing is done directly on the paper from elements havingtheir printing surfaces in relief, and involves the use of printing inkswhich are solutions and/or dispersions of organic dyestuil's or mineraldyestuils in volatile solvents and relates also to improved relievoprinting elements for carrying out such method.

Heretofore, dyestufl's of the character referred to, have been employedwith rubber printing elements in the production ofcolored paper forwrapping purposes, paper bags, etc., and although ior this purpose itsuse has been extensive. it has been quite definitely limited to thisfield. Inks of this character present many advantages over the usualvarnish inks used in letter press work because of the simpleconstruction and operation of the inking apparatus required, and alsobecause of the quick drying properties of the inks as a result of whichsmudging of the freshly printed sheets is substantially avoided. Becauseof the many advantages inherent in such inks, it has been proposed touse them in high speed rotary presses for newspaper and illustrationwork, where heretofore varnish inks have been exclusively employed.

In the production of colored paper,'wherein the use of solutions ordispersions of organic dyestuifs or mineral dyestufis in volatilesolvents is common, rubber printing elements have been employed aspreviously stated, the reason being the particular afinity whichsolutions of this character have for the rubber surface. In adaptinghigh speed rotary presses for use with such inks in the printing oi?newspapers, illustration worlr, and the like, the some practice has beenfollowed, that is, rubber printing elements havebeen used, the generalpractice being to use a metal printing element for the black varnishinks and arubber printing element for the color work, the rubberprinting elements being used mostly in combinatlon with boolr printingpresses, as auxiliary printing mechanisms. Metal printing elements,

such as stereotypes and electrotypes have been avoided with solutionsand dispersions oi organic and mineral dyestuffs, because thesesolutions, being substantially of the consistency of water, are repelledby the metal surfaces, the solutions being deposited thereon in finedisconnected globules instead of in thin uniform coatings necessary forgood printing, whereas in the instance of etched surfaces, it has beenfound that the solutions flow down into the etched recesses, fillingthem up and destroying the tones of the printed reproductions.

It has been found however, that there are many disadvantages inherent inthe rubber printing elements when used for newspaper or illustration 5work, since when even the slightest pressure is used, the screen pointsor the lines of a line drawing or of aletter character yield or areotherwise deformed. To overcome this difliculty, it has been proposed toreinforce the rubber printing forms with insertions of textile fabrics,wire woven fabrics, or the like, or by vulcanizing very thin rubberforms on metal plates, but even with such expedients, the necessaryrigidity in the relief portions can not be attained, or at the most,only to a very small degree. Another disadvantage in the rubber printingelements 101' rotary presses is that the elements can only be made flatand in mounting on the cylinder must be bent to suit the diameter of thecylinder, with the result that distortion in the face of the element isunavoidable.

Still another disadvantage in the use of rubber printing elementsresides in the difficulty and expense of manufacture. Special equipment,such as vulcanizing presses and other accessories are necessary, as wellas a special technique which can be acquired only after considerableexperience in the work. For these and other reasons, the use. of rubberprinting elements in book printing plants has been found uneconomical.In newspaper printing, there is the further disadvantage that where itis desired to print, say a red he s t line, it has been found verydifiicult to prepare the rubber printing forms with the necessary speed,even when rubber is used.

Contrary to the procedure that has been here toiore followed, it isproposed, in accordance with the present invention, to use with inlisconsisting of solutions and/or dispersions of organic dye- 4o stuffs ormineral dyestufis in volatile solvents, such as methanol, ethyl alcoholand acetone or water, with or without the addition of suitable bindingagents, the ordinary plates of stereotype metal, electrotypes or etchedlined or screened plates. lll necessary, the stereotypes andelectrotypcs should be degreased before use with suitable solvents, suchas alcohol, and particularly in the case of large or unbroken surfaces,should be smoothly polished with polishing media, as for instance,polishing rubber, so as to insure that the inks will be properly takenup and given 0d. Proper polishing of the plates will obviate thetendency of the ink to be depositedin globules.

In the case of etched plates, the etching must be at rapidly vulcanizing35 somewhat deeper, say approximately one and one-half times thatnormally used with varnish inks. The deeper etched plates will allow theink to run down into the etched cavities without filling them up anddestroying the tones. Extensive experiments made by the inventor haveproved that when printing with inks, which are solutions and/ordispersions of organic dyestuffs or mineral dyestufis 'in volatilesolvents, 10. from printing elements of stereotype metal or fromelectrotypes or etched plates, it is possible to obtain an inking equalto that of rubber printing plates, while the accuracy of the impressionis considerably greater than with the known rubber 15 printing elements.It is assumed, of course, that suitable stereotype plates or electrotypeplates are used, in which the surface hasa very high degree ofsmoothness and freedom from pores. The concentration of the inks must,when printing 20 letter press and line drawings, be greater than whenprinting large or unbroken surfaces.

One of the advantages of the invention, as com pared with the use ofrubber printing elements, resides in the fact that printing elementsmade 25 of stereo metal and the electrotypes are superior in durability,and consequently will have longer life. The screen points and the linesof an etched plate also have the same qualities. For best re- ,uitshowever, the printing pressures should be 30 r latively light and evenlyapplied. The appli- 1 c tion of the ink to the printing-element is; alsosimplified, in that it is necessary only to have a single applyingroller in'contact with the printing element and which transfers the inkdirect- 35 1y from-the immersed roller which dips intothe ink box, buthere again the pressure of the inking roller on the printing elementshould be comparatively light and evenly applied for the best results.Also, the distortion in the face of the 40 printing element from bendingon the printing cylinder in rotary machines, is avoided, since the metalelements are preshaped tofit the cylinders.

A further advantageof the invention is that the existing stereotype orelectrotype arrange- 5 ments in printing plants can be used without anyalteration for the production of, the printing forms, except for thepolishing operation which, as previously stated, may be necessary toenable the inks which consist of the organic or mineral 50 dyestuffsdissolved or dispersed in 'volatile solutions to be picked up by theprinting elements. Finally, stereotype plates for rotary newspaperpresses can be made in a considerably shorter time than thecorresponding rubber printing ele- 55 ments, so that it is possible toproduce actual prints, such as head lines, when using inks of thischaracter in the limited time required for such work.

Referring to the drawings:

60 Fig. 1 is a diagrammatic view of a rotary typographic press suitablefor the practice of the in-. vention; and

Figs. 2, 3 and 4 show, respectively, partial sectional views of anetchedrelievo plate, an elec- 5 trotype plate and a stereotype plate,and which may be used in the press in practicing the invention.

As shown in Fig. 1, a paper web A is fed between an impression cylinder13 and a printing 70 cylinder C, the latter bearing the printing platesfrom which the impression is transferred to the paper web. The printingcylinder, as usual,v is inked by means of an applying roller D rotatingwith the same peripheral speed as the printing 75 cylinder and arrangedfor light tangential contact therewith. The ink is contained in a troughE of the usual character from which the ink is picked up by a fountainroller F, arranged to rotate therein. In a typographic press utilizingordinary varnish inks, there is a train of rollers 5 between thefountain roller and the applying roller in direct contact with theprlnting'cylinder in order that the ink, which is of a heavy or thickconsistency, can be rolled down for application in a thin film to theprinting cylinder. In accordance with the present invention, however,the applying roller D in contact with the printing cylinder C alsocontacts directly with the fountain roller F, this being possiblebecause of the fact that. the printing ink used in practicing 15 thepresent invention is substantially of the consistency of water, andconsequently does not require the rolling down and thinning out actionthat is required when varnish inks are used.

The method of the invention can be practiced by the use of any suitablemetal'typographic surface. Thus, by way of example in Fig. 2, there isillustrated an etched screened relievo copper plate G which is virtuallythe same as the ordinary copper half-tone except that the etching issomewhat deeper, so that the highly fluid ink can run down into theetched recesses without filling them up to the .level of the type highprinting surface. It will be readily seen that if the etched recesseswere filled up completely, the effect of the dot configuration would belost with a consequent deleterious effect in the rendering of the tonesby the plate. An etched copper or nine line plate can also be used incarrying out the method. 1 The electrotype plate (see Fig. 3) is thesame as that ordinarily used and consists of an electroplated shell Hcarrying the printing impression fastened to a backing element J whichrenders the printing surface type high. The only step 40 necessary tomake the ordinary electrotype plate suitable for use with the inksherein dealt with is that of rendering the printing surface capable ofpicking up the highly iiuid ink in a thin film of uniform thickness'overthe entire printing surface. This can be done by degreasing the platebefore use and by polishing the printing surface to the extent necessaryto produce the desired result.

The stereotype plate K shown in Fig. 4 is likewise of the usualcharacter and is prepared for use in the instant process by degreasingand polishing the surface, as in the case of the electrotype plate.

While the plates herein illustrated have been shown flat, it will beunderstood that when they are used in a rotary press, they will be madein conformance with the usual practice followed in adapting such platesto a cylindrical printing form.

With regard to the inks herein dealt with, it might be stated that theyare exceptionally well adapted for printing, say a colored border on thewhite margin of a newspaper, as a result of the fact that the ink driesimmediately. When varnish inks are used, they do not dry in therequisitely short time, so that printing on a white margin with varnishcolors is impossible, owing tothe smudging which would occur.

By far, one of the greatest advantages flowing from the use of the inksherein dealt with is in their application to multi-color printing. Theseinks being transparent, will permit those printed first to show throughthose subsequently printed, so that true color combinations arereproduced,

mechanical manufacture called "wrong covering" due to the covering powerof the separate varnish one above the other. Errors may also occur inthe individual color separation negatives obtained by three colorphotography. Finally, there may be errors in screening. All thesesources of error could not be observed and avoided independently in theseparate prints heretofore, but could only be removed by lengthycorrection during the etching of the plates. As a result, themanufacture of etched plates for three color printing required a longtime, for example, ten to fifteen days.

When transparent inks are employed however, the error resulting fromwrong covering is obviated as a result of the character of the ink,while the 'other'errors can be observed independently and thecorrections made prior to the final etching process, with the resultthat the photoof etched plates of correct color values can be carriedout in a small fraction of the time heretofore required, for example, ina few hours.

In manufacturing screened plates for three color photography,- the threecolor separation negatives are obtained in the usual way and printed onordinary white non-transparent photographic paper. Thereafter, visibleprints in black and white are obtained from'the three color separationnegatives and can be reduced or enlarged to the size desired for theetched plates. These visible prints make it possible for the operator toobserve whether thecolor distribution is correct in the three separationnegatives or'whether alterations have to be made. If B1?- terations arerequired, they can be made in a simple manner by raising or lowering thecolor values on the visible prints, thus eliminating the re-touching inthe final plate for removing individual colors and varying tones, a stepwhich is now necessary in the manufacture of ordinary multi-colorplates. From these three positives or negatives, three screen negativesare made which can be made denser or lighter, as required by varying theillumination. In this way, the screening errors are eliminated. Thescreen negatives arethen printed in the usual way on the metal plates,for example, zinc or copper plates, having a light sensitive colloidlayer, and the printed plates then etched without covering andimmediately proved. The covering of the etched plates and the use ofmechanical tools generally em-- ployed for voiding the covering errorsis thus avoided. The plates are etched somewhat deeper than usual forthe reasons hereinbefore set forth In addition to the saving in time,there is a further advantage, namely, in that only three colors arerequired for printing the usual run of work and that a better graduationof the half tones is obtained, so that the individual color grades comeout more pleasingly. Obviously, more colors can be used for obtainingparticular color values.

In the foregoing specification, the method of the invention has beendescribed merely by way of example, and obviously many variations andmodifications may be made therein which will still be comprised withinthe spirit of the invengraphic web press, three color photography. Thefirst is. the soinks which are printed tion. It is to be understood,therefore, that the invention is not limited, except insofar as suchlimitations are specified in the appended claims.

Having thus described my invention, hat I claim is:

1. The art of printing with a rotary typowherein the relief surfaces ofthe printing element are coated with an ink which is transferreddirectly to the paper web, characterized in this that the printingelement is metal and that the ink is a water-thin, quickdrying solutionof dyestuff such as heretofore has been used in a rotary typographic webpress only with rubber printing elements.

2. The art of printing with a rotary typographic web press, wherein therelief surfaces of the printing element are coated with an ink which istransferred directly to the paper web, characterized in this that theprinting element is metal with'an etched printing surface and that theink is a water-thin, quick-drying solution of dyestuif such asheretofore has been used in a rotary typographic web press only withrubber printing elements.

3. The art of printing with a rotary typo graphic web press, wherein therelief surfaces of the printing element are coated with an ink which istransferred directly to the paper web characterlzed in this that theprinting element is metal with an etched screened printing surface andthat the ink is a water-thin, quick-drying solution of dyestuff such asheretofore'has been used in a rotary typographic web press only withrubber printing elements.

4. The art of printing with a rotary typoaphic web press, wherein therelief surfaces of the printing element are coated with an ink which istransferred directly to the paper web, characterized in this that theprinting element is metal with a screened printing surface etchedsubstantially greater than necessary when varnish inks are used and thatthe ink is a water" thin, quick-drying solution of dyestuffs such asheretofore has been used in a rotary typographic web press only withrubber printing elements.

5. The art of printing with a rotary typo graphic web press, wherein therelief surfaces of the printing element are coated with an ink which istransferred directly to the paper web, characterized in this that theprinting element is metal with a screened printing surface etchedapproximately one and one-half times greater than necessary when varnishinks are used and that the ink is a water-thin, quick-drying solu. tionof'dyestuff such as heretofore has been used in a rotary typographic Webpress only with ruhber printing elements.

6. The art of printing subjects having variations both as to color andtone, with a rr a r-y typographic web press wherein the relief surfacesof the printing element are coated with different colored ink which issuperposed one color over the other directly on the paper web, cacterized in this that the printing elements are metal and have theirprinting surfaces etched variably depending upon the gradations of thegraphic web press,

thin, quick-drying solution of dyestufl such as heretofore has been usedin a rotary typographic web. press only with rubber printing elements.

8.The art of printing with a. rotary typowherein the relief surfaces ofthe printing element are coated with an ink which is transferreddirectly to the paper web, characterized in this that the printingelement is a metal stereotype with its printing surface highly polished,and that the ink is a waterthin, quick-drying solution of dyestuffs suchas heretofore has been used in a rotary typographic web press only withrubber printing elements.

9. The art of printing 'with a rotary "typographic web press, whereinthe relief surfaces of the printing element are coated with an ink whichis transferred directly to the paper web,

Patent No. 2,158,705.

WALTER HATUSCHKE.

characterized in this that the printing element is an electrotype andthat the ink is a waterthin, quick-drying solution of dyestufl such asheretofore has been used in a rotary typographic web press only withrubber printing elements.

10-. The art of printing with a rotary typographic web press, whereinthe relief surfaces of the printing element are coated with an ink whichis transferred directly to the paper web, ,characterized in this thatthe printing element is metal and free from grease and that the ink is awater-thin, quick-drying solution of a dyestufl such as heretofore hasbeen used in a rotary typographic web press only with rubber printingelements.

' WALTER MATUSCI-IKE.

CERTIFICATE OF CORRECTION.

I November 29, 1958.

I It is hereby certified that error appears lnthe printed specificationof the above numbered patent re'c uiring correction as follows: Page 5-,

"dyestuffs" read dye stuff; page LL, first column,

column, line 55, claim h, for 6', for "element" read elements;

second line 61, claim line 11, claim 8 for the word" "dyestuffs" readdyestuff;' and that the said Letters Patent should be "read with thiscorrection thereinthat'the same may conform to the record of the case inthe Patent Office.

Signed'and sealed this 10th day of January, A. D. 1959.

v 4 (Seal) Henry Van Arsdalo J t v Acting Commissioner of Patents

